Are there all-in-one Minoxidil+Ketoconazole commercial lotions?
Which brands? Where to buy?

Can you DIY?
I have some chemistry background and think that the Ethyl Alcohol + Propylene Glycol will allow for a LITTLE Keto to stay in solution.
My only concern would be Keto slowly cross-reacting with Minox over time. Maybe not much of a worry if there are commercial lotions already in the market.

Is 1% Ketoconazole enough for a lotion?
Since you don't wash it away (unlike the shampoo) you need less of it.
So I think I can either add pure Ketoconazole USP powder to existing Rogaine (or generics) or brew it all from starch.

The amazing results seeing on a paper where done with the 2 % cream. So I should go to the 2 %.
It will not react with Minox, I used it for tons of years and now I re started ( minoxidl 5 % ketoconazole 2 % lotion ) .

Here you have a really cool site of Pharmacist that made what it is call it " magistral " in Spanish ( I bet there are a similar site in english ) . It is in Spanish but it have really cool information ( may be you can use the google translator ) on how to compound different hair lotion including how much PG, how much Alcohol, how much water, etc :
http://www.formulacionmagistral.org/?s=minoxidil
Here you have a typical vehicle where you can put both drugs ( Minoxidil and ketoconazole ) :
Propilenglicol, 25 %
purify Water, 15 %
Alcohol (96º) csp, 100 ml ( csp means you reach he 100 ml with alcahol , keep in mind that the drugs have some volume, so that is why they use c.s.p , "cantidad suficiente para " in Spanish that in english should be "enough quantity to reach the 100 ml ")

If you want to go even easier, simple get the ketoconazole and dissolve it on the Rogain lotion. If you want to go even easier, apply minoxidil and a couple of minutes laters apply the ketoconazole cream . There are also sites where you can get it contact with a doctor that will give you a prescription to compound the lotion in a pharmacy.